Process for producing carbonaceous material



' o in the I bonaceous material, such as 18 obtained from Patented Apr. 18, 1933 UNITED STATES PATENT oFFIcE ALFRED) OBERLE, OF KANSAS CITY, MISSOURI P BOCESS FOB PBOD'UCIN G OARBONACEOUS MATERIAL Io Drawing.

m lecting during the destructive distillation or.

cracking and partial or complete combustion of mineral oils or their derivatives, and carbon separated by distilling, filtering, centrifuging, burning, evaporating, heating iii-gem l eral, oxidizing, extracting, refining, precipitating and fiotatingresidual andlight mineral oils or their derivatives in the form of a powder, a hard sponge-like material, or a semi-liquid pasty mass, or irregular masses to produce active carbon.- 7

Among the salient objects of the invention,

is to provide a process in which carbonaceous material of this character is relieved of any gaseous, volatile, liquid, tarry and pitchy hydrocarbons or impurities such as sulphur or sulphur compounds and innumerable other materials, by heat treatment under atmospheric or su eratmospheric pressures, or in vacuum in t e presence of r water, activating as'es, activating salts, activating metals or t eir oxides, chlorides or hydroxides, silicious and calcareous material, mineral acids and solvents, in order to produce a highly active carbon.

The process for the treatment of the carbonaceous material will vary due to impurities present, thepurpose for which the product is to be used and the relative cost of treatment. 1

The temperatures used in this grocessvary from a minimum of about 100 to a-maximum of about 200090. Very wet carbonaceous material will stand a maximum tem- 5 Erature, especially if the time factor 18 short.

aximum temperatures are also advantageously used where steam is employed; Mimmum temperatures areindic'ated in cases where hot air is used to initiate combustion pores ofrelatively dry, porous car- 4 Application filed August 11, 1928. Serial No. 299,100.

oil burners or in vapor phase cracking, in the form of pumice-stone-like chunks. Low temperatures are also suflicient where the carbonaceous material is treated with sulphuric acid, nitric acid, or mixtures of the two. In this case a reaction will set in, almost immediately, accompanied by more or less foaming and boiling and lasting for quite some time. Carbonaceous material which has been produced under conditionsiof high temperature needs often only a mild but prolonged temperature treatment such as afterlowing.

It may be said, in general, that ry heat treatment has to be carried out at considerably lower temperatures than steam heat treatment and that prolonged treatmentmust be carried out at minimum tem eratures whereas very short treatments may benefit by the use of maximum temperatures. It is important that temperatures, at which the particular carbonaceous material undergoing treatment ma change to graphitic or coke form, be avoi ed.

Wherever there is a-possibility of the volatiles present in the carbonaceous material breaking down into secondary carbons, temperatures should be kept below 300 C. until such volatiles are removed. This may be ascertained by the use of a suitable con- 80 denser.

In cases where the carbonaceous material has been acid treated prior to heat treatment without complete elimination of the acid, temperatures as low as 100 C. are efiectively used. Where hosphoric acid has been used to activate t e carbonaceous material, itis of special importance to regulate the temperature applied, since hosphoric, acid at temperatures below 600 4 'wil 800 C, reduction takes place, whereas at about 1000' 0. formation of phosphorus begins. Reduction in this case takes place:

at the costoi hydrogen complexes-present The cat treatment ma be carried on dehydrate the carbonaceous material while at about have anafiinity for under superatmospheric ressure, at atmospheric pressure, or un er a vacuum. A superatmospheric pressure ranging from 50 to 500 pounds may be maintained by means of extraneous inert gases, or gases having a catalytic or activating effect on the material under treatment. The greater part of the carbonaceous material available for the carrying out of this process is in the form of a fairly dry, spongy petroleum coke, and needs, after reduction in size, a treatment with superheated steam, followed by a gradual building up of pressure by means of steam, this pressure to be maintained for some time, then a gradual release of pressure to atmospheric pressure, and finally a Vac uum treatment. The sequence of the pressure treatment may be reversed, repeated or varied. Air may be admitted ad interim.

During all or part of the heat and pressure treatment the carbonaceous material may be mixed with sand, slacked, or unslacked lime, oyster or clam shells and other calcareous material, salts containing chlorine, such as zinc chloride, calcium chloride, magnesium chloride, iron chloride, molybdenum chloride, tin chloride, aluminum chloride, also the chlorides of oxides of nickel, cobalt, manganese, lead, thallium, etc., especially the oxides or chlorides derived from the elements included in the fifth group of Mendelejeffs table. It is understood, however, that the activating material is not limited, as difierent types of carbonaceous material will require different activating material. Iron, nickel, cobalt, copper, zinc, sodium, potassium, calcium, etc. may be used.

Prior or subsequent to or during the heating or heat and ressure treatment the carbonaceous material may be subjected to a treatment with a mineral acid or mixture thereof, such as, hydrochloric acid, sulphuric acid, nitric acid, phosphoric acids. With some of the carbonaceous material a violent reaction will take place during the first stages of the acid treatment, particularly where nitric acid, sulphuric acid, or a mixture of the two is being used. Where the carbonaceous product is used in the manufacture of electrical appliances, or for certain catal ical processes, it is of distinct ad vantage t at the removal of excess acids by water-washing, or heat treatment, be incomplete, since a. certain degree of acidity prior to the final heat treatment is advantageous.

In all other instances where acid treatment,

is resorted to, the acid treated material is water-washed until neutral, with or without the a plication of heat. The acid treatment may be substituted, preceded or followed by an alkali treatment. The alkali metals or their compounds may be used. Sodium, potassium, or calcium or their compounds are used advantageously.

By the uses of centrifuges, filter presses,

Vaporizers, or the like, the acid or alkali may berecovered and reused.

Some ty es of carbon require a treatment with suitable solvents of the aliphatic or aromatic hydrocarbon series and the generally known extractin agents, such as, gasoline, benzole, carbon bisulfide, xylol, anilins, pyridine, alcohols, phenols, carbon tetrachloride, ethers, chloroform, acetone, etc. or mixtures thereof. Treatment with solvents is preferably carried out before any heat and pressure treatment, but not necessarily so.

Such gases as, carbon monoxide, carbon dioxide, oxygen, h drogen, water-gas, flue gases, nitrogen, ch orine, air, wet and dry steam, or decomposed steam, or mixtures of the aforementioned, or gases containing same, may be introduced into the carbonaceous material undergoing treatment, preferably through a perforated tube arranged in such a manner in the treating vessel to bring about a maximum of turbulence in the material to be treated. These gases may serve as a vehicle for furnishing the necessary heat, for building up pressure to drive off and remove impurities, to initiate or carry out oxidation, or to function as activating or catalytic agents. I

The material to be treated may be charged continuously through a hopper or grinder into the top of a still wheredt undergoes the necessary treatment after which, it may be removed from the still for further treatment, if necessary.

The ases, vapors and volatile material given 0% are preferably led through a condenser and may be reused. The treating vessel; or still, should be provided with valves to keep the still under pressure and also with such appliances as manometers safety valves, charging and discharging tubes, thermometer wells, or pyrometer appliances which are generally used on apparatuses of tliiskind where pressure or vacuum is ap p 1e The carbonaceous material can be retreated, if necessary, and the process may be carried out continuously. The materials used in treating the carbonaceous matter are subsequently removed.

The roduct is a hi h bon, adhpted especial y uses:

1. Decolorizing carbons.

2. Medicinal carbons.

3. Condensation carbons.

4. Contact carbons.

5. Gas mask carbons.

6. Catal ic carbons.

7. Collo1dal carbons.

Each ofwhich possesses peculiar properties which vary widely in their effect, ori in and method of pre aration, such as, action by capillary attraction, effect of surface tensxon, selective aborption, catalytic actio :1, etc.

The method of treatment will vary, therefore atly as to boljggii gin of crude material. (Hydrocarns. 2. Method of production of carbonaceous material to be activated.

-a. Purpose for-wh'ch finished rdmt is -used 4. Facilities and relative cost.

The product obtained by this process has been used successfully for refining of sugar 7. water urification, treatment of casinghead gas, re ing and treatment of petroleum and its products such as, motor fuels, heavy oils,

lubricating oils, medicinal oils, for purifying gases, m making gas masks, in the treatment of edible oils, organic liquids and mineral acids, also in the treatment of waxes, glycerine, glue asv a substitute for lamp lack and as a filler.

- Iclaim as my invention: 1. Acontinuous process for producing activated carbon from carbonaceous material of a mineral oil origin, consisting in heating the carbon under super-atmospheric pressure to a temperature in excess of 100 C. 1n the'pres-' ence of an aqueous fluid, introducing an extraneous gas and withdrawing the volatile material and moisture and uncombined gases.

2. A continuous process for produc' activated carbon from carbonaceous material of a mineral oil origin, consisting in treating the carbon with a mineral acid, and heating the treated material to a temperature in excess of. 100 (3., withdrawing the volatile material,

moisture, admixtures and impurities.

3. A process for treating carbonaceous material of a mineral oil origin, produced under conditions of high temperature consisting in heating the carbon un er pressures submantially above atmospheric to a temperature in .excessof 100 0., but not exceedin 2,000 (3., withdrawing the volatile materia and moisture.

4. A continuous processfor producing activated carbon from carbonaceous material of a mineral .oil origin, consisting in heating the carbon under super-atmospheric ressure to a temperature in excess of 100 C. m the presence of an ueous fluid withdrawing the volatile material and moisture.

- 5. A continuous process for produc' activated carbon from carbonaceous material of a mineral oil origin, consisting in heating the carbon to a temperature in excess of 100 C., underfpressure up to 500 pounds, in the. resence 0 an acidulated aqueous fluid with raw? ing the volatile material and moisture.

. v ALFRED OBERLE. 

